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working in non-preemption mode, the master router that works properly can retain the
Master state. This state cannot be preempted even if the master router's priority
decreases.
The
undo vrrp vrid
virtual-router-id
preempt-mode
command is used to restore the
default preemption mode.
NOTE
Set the preemption delay value to 0 on the master router to allow it to become a backup
router immediately after its priority decreases; set the preemption delay to a non-0 value on
backup routers so that they can preempt the Master state after a specified delay. These settings
allow a period of time for status synchronization between the user-to-network link and network-
to-user link on devices on an unstable network. This prevents the situation where user devices
learn about an incorrect master router's IP address when two master routers coexist or a master/
backup VRRP switchover is performed frequently.
l
Set the interval at which a gratuitous ARP packet is sent by the master router.
1.
Run:
system-view
The system view is displayed.
2.
Run:
vrrp gratuitous-arp timeout
time
The interval at which gratuitous ARP packets are sent by the master router is set.
The gratuitous ARP packets sent by the master router carry the virtual MAC address.
By default, the master router sends a gratuitous ARP packet every 120s.
NOTE
The interval at which the master router sends a gratuitous ARP packet must be shorter than the
aging time of the ARP entry on each user device.
–
To restore the default interval at which a gratuitous ARP packet is sent, run the
undo vrrp gratuitous-arp timeout
command in the system view.
–
To disable the master router from sending gratuitous ARP packets, run the
vrrp
gratuitous-arp timeout disable
command in the system view.
----End
4.2.6 (Optional) Configuring Smooth VRRP Switching
After smooth VRRP switching is enabled, the backup Routers learn about the smooth switching
time, and retain their status within the smooth switching time, preventing service traffic loss
resulted from a master/backup VRRP switchover.
Context
If the master Router in a VRRP backup group performs an AMB/SMB switchover, the master
and backup Routers may fail to communicate with each other during the switchover. During this
period of time, the backup Router with the highest priority becomes the new master Router if
backup Routers receive no VRRP Advertisement packet after the interval at which VRRP
Advertisement packets are sent expires. In this situation, two master Routers coexist. After the
original master Router completes the AMB/SMB switchover, it detects that it has a higher
priority than the other master Router, and therefore retains the Master state. The other master v
HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
4 VRRP Configuration
Issue 02 (2014-09-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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